Back in October, it was Drogba’s successful penalty which sparked a riot in the stands of the Leopold Senghor Stadium in Dakar and caused Senegal’s 2013 Africa Cup of Nations play-off qualifier with Ivory Coast to be abandoned, with the visitors leading 6-2 on aggregate.

HEAD OVER HEELS

MOSES RATING VS SOUTHAMPTON

Was the Blues' main threat early in the game. Found space finding space and displayed some neat touches. Involved in the equaliser and scored the second. Brought off in the second half as he quietened down.

In response to the trouble, the Confederation of African Football (CAF) awarded Drogba’s men the victory and banned Senegal from the competition. For Ba, as integral to his country as he was to Newcastle, the decision presented both a disappointment and an opportunity.

With a January trip to South Africa no longer on the cards, Ba suddenly found himself free to fully capitalise on that £7 million release clause and engineer an exit from St James’ Park. For Chelsea, meanwhile, in urgent need of striking reinforcements to bolster a tired and threadbare squad, the 27-year-old became a viable, convenient and relatively inexpensive solution.

On the evidence of Saturday’s rout of Southampton, it appears a match made in heaven. Ba scored twice at St Mary’s, and only a good reflex save from Artur Boruc denied him a debut hat-trick. He also showcased the kind of physicality, movement and confidence that will make Rafa Benitez very happy with the start of his New Year business, and Fernando Torres fearful for his future.

But while the Africa Cup of Nations will not disrupt Ba’s attempts to establish himself at Stamford Bridge, Chelsea will still be affected by events in South Africa. Both Jon Obi Mikel and Victor Moses have been called up by Nigeria and, with David Luiz capably filling the void created by Mikel, it is the 22-year-old winger whose absence will be more keenly felt.

When he was prised from Wigan for a fee in the region of £9m in the summer, few believed Moses’ mid-season departure would be cause for any real concern. Chelsea had got their key business done early in the window, securing Lille golden boy Eden Hazard and Internacional wonderkid Oscar. Anyone else, it was assumed, had arrived merely to provide additional bodies and fresh legs.

Roberto Di Matteo valued Moses, but it was clear he was seen as an impact substitute, a more muscular and powerful Plan B on hand in case the sublime trio of Hazard, Oscar and Juan Mata produced less than their sensational best. Make an impact he did, scoring a crucial injury-time winner against Shakhtar Donetsk, but it was clear his starting opportunities would be limited.

But if a Chelsea player finds himself out of favour with his manager, he will invariably get another chance when the next one comes along. Di Matteo left, Benitez arrived, and Moses was duly catapulted onto centre stage. He has since featured in 12 of the Spaniard’s 13 games in charge, making nine starts.

The 22-year-old possesses a different set of skills from most of Chelsea’s other attacking players. He combines pace, flair and technical skill with a height, strength and directness in stark contrast to the likes of Mata, Hazard, Oscar and Marko Marin. Under Di Matteo, these differences prevented him breaking into the team. Under Benitez, they have made him virtually indispensable.

Believing his predecessor’s orgy of number 10s to favour beauty over practicality, Benitez routinely sacrifices one of his creative wizards, instead asking Moses to provide the width and true wingplay his team-mates are either unwilling to offer or simply incapable of delivering. Oscar is generally the man relegated to the bench but, even when Mata or Hazard are rested, Moses remains the constant.

To attribute his rapid recent rise solely to a change of manager would be unfair, however. For Moses has also improved his game significantly in almost all areas – passing, dribbling, heading, positioning, general awareness and, most noticeably, his finishing. His final season at Wigan yielded six goals. This term he already has five, including brilliantly clinical strikes against Leeds and Southampton.

As far as Benitez and his Chelsea team-mates are concerned, Moses will be missed. “You can always improve things, especially when you have injuries, and we lose two players to the African Cup of Nations,” the Blues boss told reporters on Wednesday. He knows he does not possess another player who can offer him what the 22-year-old can.

Whether Roman Abramovich decides to grant his interim manager any further reinforcements in January is an intriguing question. For now Benitez will have to make do with Ba, and the early signs are the Senegalese striker will do his best to make the interim as painless as possible.